Collapsable Portable Wireless Unit

ABSTRACT

A collapsable portable wireless unit ( 100 ) comprises an upper case ( 101 ) and a lower case ( 102 ) coupled through a hinge member ( 103 ) to open/close freely. A planar conductor ( 105 ) is arranged on the upper case ( 101 ). First and second power supply sections ( 111, 112, 103 ) are arranged on the planar conductor ( 105 ) at a specified interval. A harmonic signal distributor ( 120 ) is arranged on a circuit board ( 110 ) provided in the lower case ( 102 ) and distributes a harmonic signal to the first and second power supply sections ( 111, 112, 103 ). A phase shifter ( 121 ) sets the exciting phase of the harmonic signal in the second power supply sections ( 112, 103 ) at a value different from that of the exciting phase of the harmonic signal in the first power supply sections ( 111, 103 ).

TECHNICAL FIELD

The present invention relates to a foldable mobile wireless apparatushaving GPS receiving functions.

BACKGROUND ART

Foldable mobile phones having an upper case and a lower case connectedby a hinge member that connects and able to be opened and closed arewidely used in recent years. These foldable mobile phones have startedhaving additional functions of GPS (Global Positioning System) receivingfunctions. GPS utilizes circularly polarized waves, instead of linearlypolarized waves used in mobile phone communication. Accordingly, to haveGPS receiving functions and achieve high reception performance,circularly polarized wave antennas for GPS reception need to be mountedin the case of the foldable mobile phone.

Circularly polarized wave antennas for mobile phones are disclosed in,for example, Patent Document 1 and Patent Document 2. The circularlypolarized wave antennas disclosed in Patent Document 1 and PatentDocument 2 capture circularly polarized waves with cross-bar elementsprovided in the flip-down covers of the mobile phone. In addition, thesecircularly polarized wave antennas capture polarized waves appropriatelyin the state (hereinafter referred to as “calling state”) where the usermakes a call holding the mobile phone in his hand.

Circularly polarized wave antennas for mobile phones also include theone disclosed in Patent Document 3. The circularly polarized waveantenna disclosed in Patent Document 3 performs polarization diversityoperation by switching two cross elements provided inside the mobilephone and supplying power at a phase difference of 90 degrees.

-   Patent Document 1: Japanese Patent Application Laid-Open No.    2000-183635-   Patent Document 2: Japanese Patent Application Laid-Open No.    2000-353911-   Patent Document 3: Japanese Patent Application Laid-Open No.    2002-16433

DISCLOSURE OF INVENTION Problems to be Solved by the Invention

However, conventional foldable mobile phones require multiple antennaelements and feeding cables as circularly polarized wave antennas formobile phones, which gives problems of complicated configurations anddifficulty in miniaturization and thinning.

In order to solve the above problems, it is an object of the presentinvention to provide a thin, foldable mobile wireless apparatus thatdoes not require complicated configurations formed with multipleantennas and feeding cables for circularly polarized wave antennas formobile phones, and that provides high antenna performance in thehand-held state.

Another object of the present invention is to provide a thin, foldablemobile wireless apparatus that uses one antenna mounted in the foldablemobile wireless apparatus as a mobile phone antenna and as a circularlypolarized wave antenna, and that provides high antenna performance inthe hand-held state.

Means for Solving the Problem

A foldable mobile wireless apparatus according to the present inventionhas an upper case and a lower case, the upper case and lower case beingconnected by a hinge member and able to be opened and closed, andemploys a configuration having: a flat conductor that is provided in theupper case; a first feeding section and a second feeding section thatare provided on the flat conductor spaced by a predetermined distance; acircuit board that is provided in the lower case; a harmonic signaldistributing section that is provided on the circuit board anddistributes a harmonic signal to the first feeding section and thesecond feeding section; a harmonic signal supplying section thatsupplies the harmonic signal to the harmonic signal distributingsection; and a phase setting section that sets an excitation phase ofthe harmonic signal at the second feeding section to a different valuefrom an excitation phase of the harmonic signal at the first feedingsection.

Advantageous Effect of the Invention

The present invention provides a thin, foldable mobile wirelessapparatus that does not require complicated configurations formed withmultiple antennas and feeding cables for circularly polarized waveantennas for mobile phones, and that provides high antenna performancein the hand-held state.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic front view of a foldable mobile wireless apparatusaccording to a first embodiment of the present invention;

FIG. 2 is a schematic side view of foldable mobile wireless apparatusaccording to the first embodiment of the present invention;

FIG. 3 illustrates a state in which a user operates foldable mobilewireless apparatus according to the first embodiment of the presentinvention while holding lower case of foldable mobile wireless apparatusin his hand and watching the display screen of foldable mobile wirelessapparatus;

FIG. 4A is an image diagram illustrating an example of antenna currentdistribution in free space;

FIG. 4B is an image diagram illustrating an example of the antennacurrent distribution in the state shown in FIG. 3;

FIG. 5 shows a clockwise circularly polarized wave pattern on thevertical plane in the state shown in FIG. 4(b);

FIG. 6 is a schematic front view of a foldable mobile wireless apparatusaccording to a second embodiment of the present invention;

FIG. 7 is a schematic front view of a foldable mobile wireless apparatusaccording to a third embodiment of the present invention; and

FIG. 8 is a schematic front view of a foldable mobile wireless apparatusaccording to a fourth embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Now, embodiments of the present invention will be described in detailwith reference to the accompanying drawings.

First Embodiment

FIG. 1 is a schematic front view of a foldable mobile wireless apparatusaccording to a first embodiment of the present invention. FIG. 2 is aschematic side view of foldable mobile wireless apparatus according tothe first embodiment of the present invention.

As shown in FIG. 1, foldable mobile wireless apparatus 100 according tothe first embodiment of the present invention has upper case 101 andlower case 102. Hinge member 103 connects upper case 101 and lower case102 and allows upper case 101 and lower case 102 to be opened andclosed. Upper case 101 and lower case 102 are made of an insulatingresin. Sound hole 104, which is a sound element, is provided in thefront side (the X direction side) of upper case 101.

Flat conductor 105 is attached to upper case 101. Flat conductor 105 ismade of a light, strong metal having high conductivity (for example, amagnesium alloy). The size of flat conductor 105 is that, for example,long side L1 is 90 mm and short side L4 is about 45 mm. Upper case 101is provided with a display apparatus (not shown).

At both sides of the lower end of flat conductor 105, hinge fittings 106and 107 are provided spaced by a predetermined distance. Hinge fittings106 and 107 are fixed to flat conductor 105 with mounting screws 108 and109, respectively, mounted in screw holes of upper case 101.

Circuit board 110 is provided inside lower case 102. Feeding terminals111 and 112 are fixed at both sides of the upper end of circuit board110. Hinge fittings 113 and 114 are disposed between the upper end ofcircuit board 110 and the lower end of flat conductor 105. The upperends of feeding terminals 111 and 112 and the lower ends of hingefittings 113 and 114 are fixed by mounting screws 115 and 116 mounted inscrew holes. Hinge fittings 106 and 107 are rotatably connected to hingefittings 113 and 114 with rotating shafts 117 and 118, mounted in holes.

Hinge fittings 106, 107, 113 and 114, mounting screws 108, 109, 115 and116, and rotating shafts 117 and 118 form hinge member 103. Upper case101 and lower case 102 are connected by hinge member 103 and can beopened and closed. In other words, hinge member 103 makes foldablemobile wireless apparatus 100 foldable.

Hinge fittings 106, 107, 113 and 114, mounting screws 108, 109, 115 and116, and rotating shafts 117 and 118 are electrically connected. Feedingterminals 111 and 112 are electrically connected to mounting screws 115and 116 and hinge fittings 113 and 114 in hinge member 103. Accordingly,harmonic signals supplied to feeding terminals 111 and 112 are suppliedto hinge fittings 106 and 107.

Radio circuit 119, which is a reception circuit, is provided on circuitboard 110. Harmonic signal distributor 120 is connected to radio circuit119. Phase shifter 121 is connected to one output terminal of harmonicsignal distributor 120. Matching circuit 122 is connected between phaseshifter 121 and feeding terminal 111. Matching circuit 123 is connectedbetween the other output terminal of harmonic signal distributor 120 andfeeding terminal 112. Feeding terminals 111 and 112 are soldered tomatching circuits 122 and 123. Feeding terminals 111 and 112 maybeconnected to matching circuits 122 and 123 with springs.

The size of circuit board 110 is that, for example, long side L2 is 90mm and short side L3 is about 45 mm. A ground pattern, which providesthe ground potential of radio circuit 119, is formed practically allover circuit board 110. The ground terminals of matching circuits 122and 123 are grounded to the ground pattern on circuit board 110.

A harmonic signal from radio circuit 119 is supplied to harmonic signaldistributor 120. Harmonic signal distributor 120 supplies the harmonicsignal from radio circuit 119 to matching circuit 122 through phaseshifter 121, and to matching circuit 123. Harmonic signal distributor120 may be formed with, for example, a Wilkinson circuit, and havefunctions for splitting a high frequency signal from radio circuit 119to the same amplitude and the same phase. Matching circuits 122 and 123match the impedance of flat conductor 105 to the circuit impedance ofradio circuit 119 (generally, 50Ω).

Phase shifter 121 may be formed with, for example, lumped elements ordistributed elements. Phase shifter 121 sets the phase of the highfrequency signal supplied to matching circuit 122 to a different valuefrom the phase supplied to matching circuit 123.

Mobile phone antenna 131 is provided in an upper part of lower case 102.Matching circuit 132 for mobile phone antenna 131 and mobile phone radiocircuit 133, which is a transmission-reception circuit, are provided oncircuit board 110 in lower case 102. Matching circuit 132 is connectedto mobile phone radio circuit 133. Mobile phone antenna 131 is connectedto matching circuit 132 via hinge member 103. Mobile phone antenna 131may be provided at the upper end of upper case 101.

The above configuration enables the operation of a dipole antenna whereflat conductor 105 and circuit board 110 are supplied power at differentphases at both ends in the Y direction.

The operation of the antenna of foldable mobile wireless apparatus 100having the above configuration will now be described with the operatingfrequency being set to, for example, 1.575 GHz, which is the frequencyof GPS.

The operation of the antenna shown in FIG. 1 will be described withreference to FIGS. 3 and 4. FIG. 3 illustrates a state in which user 301operates foldable mobile wireless apparatus 100 holding lower case 102of foldable mobile wireless apparatus 100 in his hand and watching thedisplay screen of foldable mobile wireless apparatus 100.

FIG. 4(a) is an image diagram illustrating an example of antenna currentdistribution in free space. FIG. 4(b) is an image diagram illustratingan example of antenna current distribution in the hand-holding stateshown in FIG. 3. Referring to FIG. 4, dipole elements 401 and 402 modelthe ground patterns on flat conductor 105 and circuit board 110 in FIG.1 with rectangular elements to illustrate the antenna operation.

Current vectors 412 and 422 are distributed on the diagonal lines ofdipole element 401, and current vectors 413 and 423 are distributed onthe diagonal lines of dipole element 402. Current vectors 412, 413, 422and 423 are modeled on the antenna current distribution on dipoleelements 401 and 402 in consideration of the far field radiation in theX direction. Actually, currents having different amplitudes and phasesat different positions are concentrated and distributed over the ends ofdipole elements 401 and 402.

Current vectors 412 and 413 are components excited by feeding section411. Current vectors 422 and 423 are components excited by feedingsection 421.

The antenna operation in free space will now be described with referenceto FIG. 4(a). Referring to FIG. 4(a), when the far field radiation inthe X direction is taken into consideration, current vectors 412 and 413are synthesized and can be considered to have only the Z-directioncomponent. Similarly, current vectors 422 and 423 can be considered tohave only the Z-direction component. Hence, there is no physical angledifference between the current vector components excited by feedingsection 411 and feeding section 412.

In contrast, in the hand-held state, as shown in FIG. 4(b), dipoleelement 401 is covered by hand model 403 and so current vectors 413 and423 are influenced by hand model 403 and do not contribute to theradiation. Accordingly, only current vectors 412 and 422 contribute tothe radiation.

In this case, the phenomenon where current vector 412 (422) issynthesized with current vector 413 (423) such as shown in FIG. 4(a)does not occur. As a result, angle a (for example, 50 degrees) is formedbetween the current vector component excited by feeding section 411 andthe current vector component excited by feeding section 421.

The phase of the excitation signal of feeding section 411 is advancedwith respect to the phase of the excitation signal of feeding section421 by a predetermined value, so that the radiation of clockwisecircularly polarized waves in the X direction is provided. In thissituation, by adjusting the phase difference between the excitationsignals of feeding sections 411 and 421, it is possible to change themaximum radiation direction or axial characteristics of clockwisecircularly polarized wave radiation.

For example, by providing a phase difference of 130 degrees (=180degrees−α) between the excitation signals of feeding sections 411 and421, the maximum radiation of clockwise circularly polarized waves isprovided in the direction inclined 45 degrees to the Z direction fromthe X direction, as shown in radiation pattern 501 on the X-Z plane inFIG. 5.

As shown in FIG. 3, clockwise circularly polarized waves are generatedin the zenithal direction (in the Z direction in FIG. 3) in the state inwhich foldable mobile wireless apparatus 100 is held at an angle of 45degrees. Accordingly, the antenna performance appropriate for GPSreception is achieved in the hand-held state.

The antenna elements providing circular polarization characteristicsinclude only one flat conductor 105, and circuit board 110 and hingemember 103, which are essential components. Consequently, it is notnecessary to provide additional parts having complicated structures,such as multiple antenna elements and feeding cables, in order toachieve circular polarization characteristics, thereby enabling foldablemobile wireless apparatus 100 to be thinner.

The size and shape of flat conductor 105 and circuit board 110 or thephase difference in supplied currents therebetween are not limited tothe ones described above, and it is desirable to appropriately set themin accordance with required antenna performance. Flat conductor 105maybe formed with a metal frame forming part of upper case 101. Thecomponents of hinge member 103 may adopt an integrated configuration aslong as the feeding system is divided to both ends.

It is desirable to dispose the two feeding systems formed with feedingterminals 111 and 112 and hinge member 103 at both ends in the widthdirection, although certain advantages may be achieved even if the twofeeding systems are disposed in a middle part in the width direction ofupper case 101 and lower case 102, as long as the two feeding systemsare spaced by a predetermined distance (for example, equal to or longerthan about an eighth of the wavelength).

As described above, according to the first embodiment of the presentinvention, with a simple configuration in which power is supplied withharmonic signals having a predetermined phase difference at both ends offlat conductor 105 and circuit board 110, antenna performanceappropriate for GPS reception is achieved in the hand-held state.

Second Embodiment

A second embodiment of the present invention will now be described indetail with reference to the accompanying drawings. FIG. 6 is aschematic front view of foldable mobile wireless apparatus 600 accordingto the second embodiment of the present invention. The same referencenumerals are used in the second embodiment of the present invention toidentify the same components shown in the first embodiment of thepresent invention. Detailed descriptions of such components will beomitted.

As shown in FIG. 6, foldable mobile wireless apparatus 600 according tothe second embodiment of the present invention has switch circuits 601and 602 and control circuit 603, in addition to the components in thefirst embodiment of the present invention, and has radio circuit 604,instead of radio circuit 119. Furthermore, mobile phone antenna 131,matching circuit 132, and mobile phone radio circuit 133 are removed.Switch circuits 601 and 602 are connected to the input and outputterminals of phase shifter 121, respectively. Control circuit 603 isconnected to switch circuits 601 and 602. Radio circuit 604 is formedwith a transmission-reception circuit.

Switch circuits 601 and 602 have functions for switching betweensupplying harmonic signals split by harmonic signal distributor 120 tomatching circuit 122 through phase shifter 121 and directly supplyingharmonic signals to matching circuit 122 without phase shifter 121.

Control circuit 603 monitors the operation of radio circuit 604 todetect whether foldable mobile wireless apparatus 600 is used in GPSreception mode or in mail transmission-reception mode, and controlsswitch circuits 601 and 602 in accordance with the result of thedetection.

When foldable mobile wireless apparatus 600 is used in GPS receptionmode, control circuit 603 controls switch circuits 601 and 602 so as tosupply the harmonic signal split at harmonic signal distributor 120 tomatching circuit 122 through phase shifter 121. In contrast, whenfoldable mobile wireless apparatus 600 is used in mailtransmission-reception mode, control circuit 603 controls switchcircuits 601 and 602 so as to directly supply the harmonic signal splitat harmonic signal distributor 120 to matching circuit 122 without phaseshifter 121.

As a result, the phase of the harmonic signal (high frequency signal)supplied to matching circuit 122 is switched to a different value (i.e.phased power supply) or the same value (i.e. in-phase power supply) withrespect to the phase of the harmonic signal (high frequency signal)supplied to matching circuit 123.

Consequently, in the hand-held state shown in FIG. 3, polarizationcharacteristics vary depending on whether the user uses the mobile phonein GPS reception mode or in mail transmission-reception mode, which isone function of the mobile phone.

The operation of the antenna of foldable mobile wireless apparatus 600according to the second embodiment of the present invention will bedescribed next.

Referring to FIG. 6, since control circuit 603 controls switch circuits601 and 602 so as to supply the harmonic signal split by harmonic signaldistributor 120 to matching circuit 122 through phase shifter 121 whenfoldable mobile wireless apparatus 600 is used in GPS reception mode,the same advantage can be achieved as with the first embodiment of thepresent invention.

On the other hand, since control circuit 603 controls switch circuits601 and 602 so as to directly supply the harmonic signal split byharmonic signal distributor 120 to matching circuit 122 when foldablemobile wireless apparatus 600 is used in mail transmission-receptionmode, so that the phases of the harmonic signals supplied to matchingcircuits 122 and 123 are synchronize. Referring FIG. 4(b), in thehand-held state, only the current flowing in upper case 401 contributesto the far field radiation in the X direction. Current vectors 412 and422 excited by feeding sections 411 and 421 are synthesized at the samephase, thereby reinforcing the current vector component in the Zdirection.

In this state, the vertical polarized wave component is increased withfoldable mobile wireless apparatus 600 being held at an angle of 45degrees, as in the example shown in FIG. 3.

Generally, the pattern averaged gain (PAG) represented by followingEquation (1) is used as an index indicating the effective antennaperformance in the calling state of the foldable mobile wirelessapparatus. $\begin{matrix}{{PAG} = {\frac{1}{2\quad\pi}{\int_{0}^{2\quad\pi}{\left\lbrack {{G_{\theta}\left( {\frac{\pi}{2},\phi} \right)} + {\frac{1}{C_{VH}}{G_{\phi}\left( {\frac{\pi}{2},\phi} \right)}}} \right\rbrack{\mathbb{d}\phi}}}}} & \left\lbrack {{Equation}\quad 1} \right\rbrack\end{matrix}$In Equation (1), “G_(θ)(φ)” and “G_(φ)(φ)” are the harmonic signaldirectivities on the horizontal plane of the vertical polarized wavecomponent and the horizontal polarized wave component, respectively.“CVH” is a correction coefficient associated with the cross polarizedharmonic wave ratio of incoming waves arriving at the antenna (the ratioof the harmonic signal of the vertical polarized wave component to thehorizontal polarized wave component). It is known that the crosspolarization ratio is generally in a range from 4 dB to 9 dB in themultiplex-wave environment of land mobile communication. This indicatesthat the harmonic signal of the vertical polarized wave of an incomingwave is 4 dB to 9 dB higher than the harmonic signal of the horizontalpolarized wave.

Accordingly, Equation (1) means that the vertical polarized wavecomponent is weighted to average the harmonic signal directivities onthe horizontal plane. It is hereinafter assumed that “CVH” is 9 dB. Withthe antenna for mobile wireless apparatus, increasing the level of thevertical polarized wave component while in use gives a higher PAG.

According to the second embodiment of the present invention, thevertical component increases when power is supplied to the two feedingsections at the same phase, and, as a result, high PAG (around −4 dB)can be achieved. Hence, according to the second embodiment of thepresent invention, by controlling the phase shift between the twofeeding sections, one antenna can be used as a mobile phone antenna andas a circularly polarized wave antenna, and, furthermore, optimalpolarization characteristics can be achieved in accordance with thestate of use of foldable mobile wireless apparatus 600. In addition,according to the second embodiment of the present invention, by usingone antenna as a mobile phone antenna and as a GPS antenna, foldablemobile wireless apparatus 600 can be made smaller and thinner.

Although a configuration has been described with the second embodimentof the present invention where the phase of the harmonic signal suppliedto the −Y side is changed, the same advantage can be achieved with aconfiguration where the changed is made to the supply to the Y side orwith a configuration where the phases of harmonic signals at the twofeeding sections are changed together.

Third Embodiment

A third embodiment of the present invention will now be described indetail with reference to the accompanying drawings. FIG. 7 is aschematic front view of foldable mobile wireless apparatus 700 accordingto the third embodiment of the present invention. The same referencenumerals are used in the third embodiment of the present invention toidentify the same components shown in the first embodiment of thepresent invention. Detailed descriptions of such components will beomitted.

As shown in FIG. 7, foldable mobile wireless apparatus 700 according tothe third embodiment of the present invention has, with respect to thefirst embodiment of the present invention, phase difference controlcircuit 701 instead of phase shifter 121 and adds inclination anglesensor 702. Inclination angle sensor 702 is connected to phasedifference control circuit 701.

Inclination angle sensor 702 detects the inclination angle of foldablemobile wireless apparatus 700 and generates a value of the detectedinclination angle and supplies the generated value to phase differencecontrol circuit 701. Inclination angle sensor 702 is formed with, forexample, a triaxial gyro sensor. Inclination angle sensor 702 detectsthe inclination angle of foldable mobile wireless apparatus 700 inthree-dimensional space and generates the value of the detectedinclination angle.

Phase difference control circuit 701 controls the phase differencebetween the harmonic signals supplied to the two feeding terminals 111and 112 in accordance with the value of the inclination angle detectedby inclination angle sensor 702.

The third embodiment of the present invention is applicable to thesecond embodiment of the present invention.

As described above, according to the third embodiment of the presentinvention, since the polarized waves can be optimized in accordance withthe inclination angle of foldable mobile wireless apparatus 700, whichvaries depending on the state of use of foldable mobile wirelessapparatus 700, it is possible to always ensure high antenna performance.

Fourth Embodiment

A fourth embodiment of the present invention will now be described indetail with reference to the accompanying drawings. FIG. 8 is aschematic front view of foldable mobile wireless apparatus 800 accordingto the fourth embodiment of the present invention. The same referencenumerals are used in the fourth embodiment of the present invention toidentify the same components shown in the first embodiment of thepresent invention. Detailed descriptions of such components will beomitted.

As shown in FIG. 8, foldable mobile wireless apparatus 800 according tothe fourth embodiment of the present invention has, with respect to thefirst embodiment, L-shaped conductor 801 and L-shaped conductor 802,instead of flat conductor 105.

L-shaped conductor 801 and L-shaped conductor 802 are spaced by apredetermined distance in upper case 101 and are arranged so as to havedifferent main polarized wave directions. L-shaped conductors 801 and802 are fixed to hinge fittings 106 and 107 with mounting screws 108 and109, mounted in screw holes of upper case 101.

The operation of the antenna of foldable mobile wireless apparatus 800according to the fourth embodiment of the present invention, shown inFIG. 8, can be described using current vectors modeling currentdistribution on antenna elements in consideration of the far fieldradiation, as in the operation of the antenna shown in FIG. 1.

Using the above model, the current distributed on L-shaped conductor 801can be modeled with current vectors distributed on lines connecting thefeeding section and the tip of L-shaped conductor 801. The currentdistributed over L-shaped conductor 802 can also be similarly modeled.

The phase of an excitation signal of L-shaped conductor 801 is advancedwith respect to the phase of an excitation signal of L-shaped conductor802 by a predetermined value, so that clockwise circularly polarizedwaves are provided in the X direction side. In this situation, byadjusting the phase difference between the excitation signals ofL-shaped conductors 801 and 802, it is possible to change the maximumradiation direction or axial characteristics of clockwise circularlypolarized wave radiation.

The components forming the antenna elements providing circularpolarization characteristics include only L-shaped conductors 801 and802, and circuit board 110 and hinge member 103, which are essentialcomponents, thus eliminating the need for parts including feedingcables.

Although both antenna elements (L-shaped conductors 801 and 802) areL-shaped in the fourth embodiment of the present invention, similarcharacteristics can be achieved even if the angle making the L-shape isnot 90 degrees. In addition, with the fourth embodiment of the presentinvention, even if both antenna elements have linear shapes, instead ofL-shapes, as long as the antenna elements are disposed so as to havedifferent main polarized wave directions, the same advantage can beachieved. Furthermore, the same advantage can be achieved in the fourthembodiment of the present invention even if both antenna elements havecursive shapes, instead of linear shapes, as long as the antennaelements are disposed so as to have different main polarizationdirections.

The fourth embodiment of the present invention is applicable to thesecond and third embodiments of the present invention.

Foldable mobile wireless apparatus 800 according to the fourthembodiment of the present invention can provide not only circularlypolarized waves but also linearly polarized waves used in communicationwith foldable mobile wireless apparatus 800, by adjusting the phasedifference of excitation signals between two antenna elements. Forexample, with foldable mobile wireless apparatus 800, when power issupplied to the both antenna elements at the same phase, the verticalpolarized wave component increases and high PAG can be achieved in thestate of use for mail such as shown in FIG. 3.

In contrast, with foldable mobile wireless apparatus 800, when power issupplied to the both antenna elements at reverse phases, the horizontalpolarized wave component increases. Generally, since the mobile phone islikely to be held at an inclination of about 60 degrees in the callingstate in which the user makes a call while holding foldable mobilewireless apparatus (foldable mobile phone) in his left or right hand andmaking foldable mobile wireless apparatus (foldable mobile phone) closeto his ear and mouth, the horizontal polarized wave component in freespace becomes the vertical polarized wave component in the callingstate. Accordingly, with foldable mobile wireless apparatus 800, bysupplying power to the both antennas at reverse phases and increasingthe horizontal polarized wave component, the vertical polarized wavecomponent is reinforced in the calling state, so that high PAG can beachieved.

Consequently, according to the fourth embodiment of the presentinvention, by appropriately controlling the phase difference inexcitation signals between the two antenna elements, the antennaelements can be used as a mobile phone antenna and as a circularlypolarized wave antenna, so that it is possible to make foldable mobilewireless apparatus 800 smaller and provide optimal polarizationcharacteristics in accordance with the state of use of foldable mobilewireless apparatus 800.

According to a first aspect of the present invention, a foldable mobilewireless has an upper case and a lower case, the upper case and lowercase being connected by a hinge member and able to be opened and closed,and this foldable mobile wireless apparatus employs a configurationhaving: a flat conductor that is provided in the upper case; a firstfeeding section and a second feeding section that are provided on theflat conductor spaced by a predetermined distance; a circuit board thatis provided in the lower case; a harmonic signal distributing sectionthat is provided on the circuit board and distributes a harmonic signalto the first feeding section and the second feeding section; a harmonicsignal supplying section that supplies the harmonic signal to theharmonic signal distributing section; and a phase setting section thatsets an excitation phase of the harmonic signal at the second feedingsection to a different value from an excitation phase of the harmonicsignal at the first feeding section.

With this configuration, it is possible to provide a thin, foldablemobile wireless apparatus that does not require complicatedconfigurations formed with multiple antennas and feeding cables forcircularly polarized wave antennas for mobile phones, and that provideshigh antenna performance in the hand-held state.

According to a second aspect of the present invention, the foldablemobile wireless apparatus of the first aspect of the present inventionfurther includes a phase difference controlling section that controls aphase difference between the harmonic signal excited by the firstfeeding section and the harmonic signal excited by the second feedingsection.

With this configuration, in addition to the advantage of the firstaspect of the present invention, it is possible to provide a thin,foldable mobile wireless apparatus that uses one antenna mounted in thefoldable mobile wireless apparatus as a mobile phone antenna and as acircularly polarized wave antenna, and that provides high antennaperformance in the hand-held state.

According to a third aspect of the present invention, the foldablemobile wireless apparatus according to the first aspect of the presentinvention further includes an inclination angle detection section thatdetects an inclination angle of the foldable mobile wireless apparatusand generates a value of the detected inclination angle, and, in thisfoldable mobile wireless apparatus, the phase difference controllingsection controls the phase difference in accordance with the value ofthe inclination angle detected by the inclination angle detectionsection.

With this configuration, in addition to the advantage of the firstaspect of the present invention, it is possible to provide optimalpolarization characteristics in accordance with the inclination angle ofthe foldable mobile wireless apparatus.

According to a fourth aspect of the present invention, a foldable mobilewireless apparatus has an upper case and a lower case, the upper caseand lower case being connected by a hinge member and able to be openedand closed, and this foldable mobile wireless apparatus employs aconfiguration having: a first conductor and a second conductor that arearranged in the upper case spaced by a predetermined distance such thatmain polarized wave directions differ; a first feeding section and asecond feeding section that are provided on the first conductor and thesecond conductor; a circuit board that is provided in the lower case; aharmonic signal distributing section that is provided on the circuitboard and distributes a harmonic signal to the first feeding section andthe second feeding section; a harmonic signal supplying section thatsupplies the harmonic signal to the harmonic signal distributingsection; and a phase setting section that sets an excitation phase ofthe harmonic signal at the second feeding section to a different valuefrom an excitation phase of the harmonic signal at the first feedingsection.

With this configuration, it is possible to provide a thin, foldablemobile wireless apparatus that does not require complicatedconfigurations formed with multiple antennas and feeding cables forcircularly polarized wave antennas for mobile phones, and that provideshigh antenna performance in the hand-held state.

The present application is based on Japanese Patent Application No.2004-130328 filed on Apr. 26, 2004, the entire content of which isincorporated herein by reference.

INDUSTRIAL APPLICABILITY

The present invention is suitable for use in a thin, foldable mobilewireless apparatus that does not require complicated configurationsformed with multiple antennas and feeding cables for circularlypolarized wave antennas for mobile phones, and that provides highantenna performance in the hand-held state.

1. A foldable mobile wireless apparatus having an upper case and a lowercase, said upper case and lower case being connected by a hinge memberand able to be opened and closed, the foldable mobile wireless apparatuscomprising: a flat conductor that is provided in the upper case; a firstfeeding section and a second feeding section that are provided on theflat conductor spaced by a predetermined distance; a circuit board thatis provided in the lower case; a harmonic signal distributing sectionthat is provided on the circuit board and distributes a harmonic signalto the first feeding section and the second feeding section; a harmonicsignal supplying section that supplies the harmonic signal to theharmonic signal distributing section; and a phase setting section thatsets an excitation phase of the harmonic signal at the second feedingsection to a different value from an excitation phase of the harmonicsignal at the first feeding section.
 2. The foldable mobile wirelessapparatus according to claim 1, further comprising a phase differencecontrolling section that controls a phase difference between theharmonic signal excited by the first feeding section and the harmonicsignal excited by the second feeding section.
 3. The foldable mobilewireless apparatus according to claim 1, further comprising aninclination angle detection section that detects an inclination angle ofthe foldable mobile wireless apparatus and generates a value of thedetected inclination angle, wherein the phase difference controllingsection controls the phase difference in accordance with the value ofthe inclination angle detected by the inclination angle detectionsection.
 4. A foldable mobile wireless apparatus having an upper caseand a lower case, said upper case and lower case being connected by ahinge member and able to be opened and closed, the foldable mobilewireless apparatus comprising: a first conductor and a second conductorthat are arranged in the upper case spaced by a predetermined distancesuch that main polarized wave directions differ; a first feeding sectionand a second feeding section that are provided on the first conductorand the second conductor; a circuit board that is provided in the lowercase; a harmonic signal distributing section that is provided on thecircuit board and distributes a harmonic signal to the first feedingsection and the second feeding section; a harmonic signal supplyingsection that supplies the harmonic signal to the harmonic signaldistributing section; and a phase setting section that sets anexcitation phase of the harmonic signal at the second feeding section toa different value from an excitation phase of the harmonic signal at thefirst feeding section.